Method of and apparatus for translating electrical variations.



P. C. HEWITT.

METHOD OF AND APPARATUS FOR TRANSLATING ELECTRICAL VARIATIONS.

APPLICATION FILED MAR. 30, 1907- Patented June 29, 1915.

7 SHEETSSHE ET I.

W/TNESSES P. C. HEWITT.

METHOD OF AND APPARATUS FOR TRANSLATING ELECTRICAL VARIATIONS.

APPLICATION FILED MAR. 30. 1907.

Patented June 29, 1915.

WITNESSES P. C. HEWITT.

METHOD OF AND APPARATUS FOR TRANSLATING ELECTRICAL VARIATIONS.

Patented June 29, 1915.

7 SHEETSSHEET 3.

APPLICATION FILED MAR. 30, I907.

P. c. HEWITT. METHOD OF AND APPARATUS FOR TRANSLATING ELECTRICALVARIATIONS.

APPLICATION F lLED MAR. 30, I907.

, Patented June 29, 1915.

7 SHEETS-SHEET 4.

INVENTOH ATTORNEY P. c. HEWITT. METHOD OF AND, APPARATUS FOR TRANSLATINGELECTRICAL VARIATIONS.

' APPLICATION FILED MAR. 30. 1907. j 1,144,596. Patented June 29, 1915.

7 SHEETS-SHEET 5.

lNVEA/TOH A TTOHNE Y P. c. H EW|TT; METHOD OF AND APPARATUS JFORTRANSLATING ELECTRICAL VARIATIONS.

APPLICATION FILED MAR. 30, I907.

Patented J1me 29, 1915.

7 SHEETS-SHEET 6.

- ATTORNEY .P. C. HEWITT.

METHOD OF AND APPARATUS FOR'TRANSLATING ELECTRICAL VARIATIONS.APPLICATION FILED MAR. 30, 1907.

1,144,596, A Patentedlune 29,1915.

. 7 SHEETS-SHEET I.

INVENTOH "are.

OF NEW JERSEY.

MESNE ASSIGNMENTS, T0 JERSEY. A mmnwrlolv METHOD OF AND APPARATUS FORTRANSLATING ELECTRICAL VARIATIONS.

Specification of Letters Patent.

Patented June 29, 1915.

Application filed March 30, 1907. I Serial No. 365,597.

T all w/zom it may concern:

Be it known that I, PETER Coornn HEW- ITT, a citizen of the UnitedStates, and a resident of New York city, in the county of New York andState of New York, have invented a certain new and useful Method of andApparatus for Translating Electrical Variations, of which the followingis a specification. I

My present invention involves the discovery of certain phenomenadeveloped by the flow of electric current through a gas or vapor, and itparticularly concerns the utilization of such phenomena in connectionwith electrical variations-of-all kinds and for various purposes. It isuseful in connection with very rapid and very feeble electricalvariations, and is particularly adapted to translate variations ofpotential. hen-used for detecting the oscillations in the receivingcircuit of a space telegraph or telephone system, the resultsdemonstrate extreme sensitiveness, reliability and dura-- bility,

. My invention contemplates the employment of one ormore special orauxiliary terminals, or electrodes, in operative relation to a gas orvapor carrying current, said current being supplied to the gas independently of such auxiliary terminal or terminals. The geometricalcharacteristics of the conducting vapor may be determined by the size,shape, etc, of a containing vessel and by the size and position ofelectrodes therein. The electrical characteristics of the gas or vaporare dependent upon the geometrical characteristics, upon the kind andpurity of the gas or vapor, upon the nature and material of theelectrodes, and upon the density of the vapor. The density of the vapordepends upon the temperature and pressure and the 'initia-Ld'ensity of'a .given vapor in a hermetically sealed container, may be varied throughchanges of internal.

temperature. I Normal or' initial internal temperature is dependent uponthe temperaof the surroundings. Changes oftempera ture' during operationare dependent upon the "ratio of heat generation to heat radia-' tion.The internal heat generation is dependent upon the above mentionedelectrical characteristics and upon the amount of current flowing in thevapor device. The heat .radiationis dependent upon the heat radiatingarea and the temperature of the surroundings. Hence, in the operation ofa vapor device having given geometrical and electrical characteristicsof construction, the density of the vapor is controllable by regulatingcurrent flow, heat radiating area, and temperature of the surroundings.

The reactions attending passage of current in a conducting gas or vapormay be subdivided .into three definite classes: (1)

reactions at and near the positive electrode or anode; (2) reactions inthe gas or vapor itself; and (3) reactions at and adjacent the negativeelectrode,or cathode, including reactions at the junction of thenegative dark space with the vapor carrying current from the mainpositive electrode. The separate phenomena of which the reactions at thepositive electrode or anode are made up, are numerous, and are chieflymodified by the position, size, and physical state of the anode; and bythe purity, density, and kind of gas; and also by current density in thegas. Certain of them are sensitive to magnetic action. One of thevisible-reactions of the positive electrode or anode, is a luminous ballor bush which is very sensitive to magnetic action and which tends to bea source of variation. At low densities it is very sensitive to magneticaction. The reactions in the conducting vapor itself and modificationsthereof, independent of the reactions near the electrodes, have beenbroadly stated by me. They may be modified by a magnet, especially atlow densities. The reactions of the vapor column are normally stable,and for purposes of this invention, its length, the kind of gas, the gasdensity, and the current density are chief modifying factors to beconsidered and controlled. The phenomena at the negative ottsservedunder certain conditions. A modified leakage current tlowin under lowerstress manifest when said electrode is present in a current carryingvapor having suthcient current density. The opposition or apparentresistance to this leakage current, is modified by the surface area ofthe electrode, and by the current density in the vapor adjacent thereto,and it varies in ways peculiar to itself with the nature, purity and thedensity of the vapor, and with the nature and condition of theelectrode. It varies with the temperature of the negative electrode, andif this temperature be increased to incandescence, this resistance thenreaches or comes near its limit. After the last state of resistance inthe primary condition has been reached, if the temperature of theelectrode be increased to such a point as to bring about a physical orchemical change of state of the electrode, while current, withsuflicient backing, is passing into said electrode, the reactions willchange to those of the second class; namely, those attendant upon thebroken down state of resistance, and the reactions of the negativeelectrode will then be measured by a less drop in potential. It is oftendesirable that the drop over the device be as small as possible and insuch case this latter state should serve best. This broken down state ofthe negative electrode may be attained by various expedients now wellknown in the art. Accompanying this change are the visible phenomena ofthe negative flame to which I have before called attention. The visiblephenomena consist of a bright spot on the negative electrode with aflame apparently hovering over this spot. The peculiar characteristic ofthis flame is that it tends to lie in and along the magnetic lines offorce, rather than to be twisted or distorted by them, as is usual tocurrent passing. It tends normally to project itself perpendicularlyfrom the surface of the electrode. A magnet may be used to modify oradjust the conditions at the negative electrode. The bright spot tendstolocate itself at a menis cus of an irregularity on an electrode. Theflame itself is surrounded by a dark space and when the flame is nnormal position in a right line with the vapor column, the top of theflame usually marks the boundary of the dark space where it joins theluminous positive column of conducting vapor coming from the positiveelectrode. The flame is very sensitive to electrical variations, andsuch variations may be observed when looking at it Its reactions mayalso be varied by a magnetic field and its reactions may be made usablein this way. When the positive electrode is arranged at comparativelyshort distances from the negative electrode as, for instance, whenlocated within the dark space, there may be no luminous posimenace tivecolumn, and the reactions at the positive are modified at certaindistances from the cathode and may be rendered. practicailyunnoticeable. The positive bush reaction may be practically eliminatedby these means. The length of the vapor column is decreased so that thetotal voltage drop variations in the detecting instrument, al-

though the vapor device may be operated under other conditions. ance,preferably an inductance in series with the device, is desirable, as ittends to promote stability. Moreover, a reactance in either or bothleads may serve to check the rapidly varying currents to be detected, sothat the receiving or variation circuit will be less affected by thecharacteristics of the main supply circuit. The vapor device may bestarted and regulated or controlled by any known or desired means ormethods, particularly those suitable for mercury vapor lamps and devicesheretofore invented by me. I expose within the device, supplied withcurrent through such main electrodes, a separate terminal or two or moreterminals operativelv associated with a telephone or other indicatinginstrument and with a source of variation to be detected. The relativepositions of such terminal and of the main electrodes are ofconsiderable importance because, other things being equal, the effectsof the reactions at an aux- A suitable reactiliary terminal of thistype, seem to vary with the charge in the body of the vapor,particularly in the region immediately adjacent such auxiliary terminal.The current density in the vapor varies with the total amount of currentflow between the main electrodes and also with the relative position 'orlocation of the "auxiliary terminal with will usually have the effect ofchanging the.

obtain approximately the similar effects.

And, further, if it is desired to vary the effect, increase of size inthe area of the aux iliary terminal will have an effect somewhatanalogous to increase of charge or current density in the body ofvapor-adj acent thereto. In practice these variables may always beadjusted to insure the best conditions of operation for a givencharacter of signal or other received energy, by noting the-good or illefi'ect of adjustment or change in a given direction of either of theabove factors and continuing, discontinuing, or reversing the directionof said adjustment or change untll the best effects are obtained. It isnot necessary in allcases to make an of these factors variable. Byhaving predetermined proper conditions and areas for certain work, asingle. device 'may be constructed which will embody the features andrelations desired. By increasing the main currentwhen receiving evenfaint signals, the volume of the signal may be amplified in manyarrangements of .this device. and this may be continued up to the pointwhere they begin to be obscured by other variations developed. Forinstance, in the-case of a vapor device of a type hereinafter described,wherein the main positive electrode is located, say, about 1/4 to 3/8 ofan inch from the surface of the mercury of the main negative electrodeand the auxiliary electrode is,

say 5 inches away from and above the nearest'or' said main electrodes,it may be that the best electrical condition of the vapor adjacent theauxiliary electrode, for a given character of signal or received energy,may

be attained-with approximately k5 amperes 0t" current flowing betweenthemain positiveand negative electrodes; whereas if saidauxiliary-electrode is 6-01. 7 inches away .from'saidinain electrodes,the main current fiowr'rnight have to be increased 'to approxiniately-2or?) 'amperesin order to get ap proximately equivalent conditions.Whatever "type'of device be employed for maintaining thefsupply ofcurrent'in the vapor,

such supp'ly "should, be independent of, the ,auxiharyfielectrode usedfor detecting pur+ poses. Arr-auxiliary electrode, because of itsposition er electrical connections, may

have a tendency to be a positive "or 'a negati-ve electrode withreference to the vapor,

- or, being-maintained'yat a neutral point, as

by a source of counter electromo'tive force, or by a condenser Wh10hma/y be'used as such, it may under certain conditions tend to actaseither, or alternately, as both. For" some purposes it is preferablethat it be arranged so as normally to have no current flowing eitherfrom or to it, except such currents as are the result of the action ofthe electrical variations to be-detected, and in case it is desired thatthe device should have a rectifying action, the auxiliary electrodeshould tend to oppose a prohibitive barrier to the passage of currentfrom the vapor into it. This action seems to be more complete when thecurrent flow in the vapor adjacent to it is at or near a minimum and itssurface area is not too great. There may be anormal current flow eitherto or from an auxiliary terminal, but such flow may increase internallyoriginated disturbances which tend to mask the effect when feeblevariations are to be detected, even when such current flow is checked bya condenser or counterelectromotii e force. There seems caused by suchtendency to normal current flow through the auxiliary electrode,according as the latter has the ability to act as a cathode to receivecurrent from the vapor, or as an anode to deliver current to the vapor.When having the ability to act as a cathode to allow current flow intothe auxiliary electrode, in many cases increase of such flow seems todirectly decrease sensitiveness,zand may produce disturbing indications,whereas when tending to act as an anode, 'too great increase of currentflow apparently tends to obscure the observable indications and may maskthe same under a disproportional increase of internally produceddisturbances. Such disturbances may be objectionable or they may in somecase be made to assist in detecting-certain kinds of variations. Hence,when the arrangement is such that the auxiliary electrode normally tendsto act as an anode with current normally tending to flow from it, itsarea, shape, location, and material should be such as will not give riseto an objectionable intensity of internal disturbing variations, un-

obtained Where the auxiliarv'electrode tends to act as an anode having aslight normalcurrent flow from it to the vapor, the quantity of suchcurrent being perhaps of the order of one-tenth to, say, twomilliamperes.

In such case the indications from the re .ceived energy seem to be moreintense up to a point where the increasing current causesdisproportionately increasing disturbing conditions. When any conditionof tendency to current flow to or fromv the auxiliary electrode suitablefor receiving signals, has

been attained, as, for instancawher'e there thereby checked. For mostwireless work, I

prefer to use a small condenser or a counter connected potentiometer.

Devices of the character desirable for T maintaining the currentcarrying vapor in the desired conditions, are themselves essentiallyunstable, irrespective of whether there is current HOW to .or from anauxiliary terminal; that is to say, the normal internal variations ofapparent resistance particu-' larly at the electrodes, are such as tocause electrical fluctuations, which cause very marked responses at anauxiliary electrode andin'the indicating instrument associated with it,when the negative electrode is in the low resistance or broken downstate. For this reason, it is essential to the best operation of myinvention for delicate work, that the normal, internally originatedvariations be made as small as possible and affect as little aspossible, an electrode which is in operative relation to the indicatinginstrument. To this end, the internal causes of such variations may belargely; suppressed or counteracted, and the auxiliary electrode orelectrodes may be situated so as to be but little affected by them, theindicating inst-nument being connec d to the apparatus in such manner asnot to be seriously affected by suchvariations. The indicatinginstrument may be employed with other devices serving to 'cut off suchvariations; or, if desired, all of these expedients may be employed.

' In the cases where the main negative eleci i trode is a liquidelectrode in the lowresistance condition, the wandering tendency of theflame may be fixed in various ways, as, for instance, by having aprojection from the electrode, adapted to be wetted by the" liquid andextending above the surface thereof, somewhat after the manner shown inmy prior Patent No. 758,650. By fixmg the flame, electrical variationsdue to the,

phenomena at the negative'electrode, may be modified and renderedpractically stable. The reactions at the positive 'electrodeare normallyin an unstable state and give rise to rapid electric variations, whichwhen heard in a telephone are rumbling,'rattling, crackling sounds, andmay, under certain conditions, produce clear musical notes. One means ofrendering the reactions at the main positive electrode substantiallystable, is to bring such main positive electrode in close pIil'oximityto the main negative electrode.

such'case, the visible phenomena at the mum current without becoming"unduly overheated but it should not be too large on account of the bushreaction. It may be designed to be highly heated and its temperature maybe made to affect the reactions at the negative electrode, as well asits own. The vapor column, considered by itself, rarely presents anysources of irregular or detrimental electrical variation. It isdesirable to use means to maintain the current in the vapor normallyconstant and uniform in quantity and in distribution.

The internal variations may be modified by a magnetic field external tothe device, the exact position and distanceof the magnet suitable forgiven conditions being usually determined by a few trials. The magneticfield thus employed may be made to vary the internal resistances orreactions, and will often increase the sensitiveness of the device. Thedesired direction and dis tribution of the lines of forceof the fieldmay be established by proper design and location of a single magnet, ora plurality of magnets may be used to establish a result- 100 ant field.With a ring positive electrode, it is usually desirable to have thelines of force some where about 45 degrees from the normal-direction ofthe negative electrode flame and with a disk positive electrodeapproximately parallel with such direction.

The circuits herein described, the auxiliary terminal or the describedabove provisions for suppressing internally originating fluctuations anddisturbances, are 'particularly desirable for and may one or' all beused in connection withmeans for receiving, rectifying, \relaying,magnifying, detecting, or otherwise translating electric variations, andmore particularly, feeble variations, such 5 as telephonic currents orthe received energy from electromagnetic waves of the kind used forwireless telegraphy or telephony.

. I" have discovered that when one or more separate terminals areprojected into a device having a vapor, carryin current which issupplied independently 0 such terminal, the. reactions in the device aremost sensitive to electric variations and that by connecting suchterminal to a telephone mceiver, siphon recorder, or other sensitiveindicating instrument, electric variations cause marked response on theindicating instrument and are rendered audible in a telephone.The'loudness'or, intensity of the infrom the observer. Two or moreauxiliary terminals maybe connected in parallel with each other and to atelephone or other indicatin instrument. The circuit from the auxiliaryterminal need .not be closed. A circuit lfrom the :latter to ground orto a Y capacity or to one of the main electrodes or to another auxiliaryterminal, may be used. In the case of wireless telegraph signals, thevariations may be operatively applied to the vapor deviceby merelyconnecting the receiving .circuit to a small capacity area located inthe neighborhood of the device; as, for instance, a metal plate a footsquare arranged parallel with the sideof the vapor device and, say, sixinches or more from it. Two auxiliary terminals may be connected inseries withcacli other :through the indicating instrument. Varyingresults .may be obtained when the indicating instrument is connectedbetween two or more auxiliary electrodes, by having them dissimilar as:to position, surface, or some other slight difference of electricalcondition or relation. By suitable selection of the auxiliaryelectrodes,:the latter arrangement becomes char acteristically free fromdisturbing variations and when a condenser is serially interposed, amost-delicate indicating instrument fails to be seriously disturbed byinterior disturbing variations.

In all forms showniherein the conducting gas or vapor is inclosed'in;asuitable container pre'ferablyhaving threexor more electrodes. Theelectrical reactions at the various electrodes and inithe conductingmedium may be thus caused .and controlled as desired, to enablethe-developmentv of suitable reactions .within the medium-itself for thedesired purposes andto make possible the modification and control of thereactions. The temperature and density 'of the a gas or vapor may becontrolled in any desired way, as by determining the area anddisposition of the outer radiating surfaces of'the container or by theuse of suitablecxpedients for increasing or decreasing-the heatabsorbing or heat imparting power of the sur roundings, such asjacketing or immersing in heating or cooling baths parts or all of thedevice.

In all of the forms shown herein, the conducting medium is referred toas a gas or vapor medium contained between electrodes in an.hermetically sealed vessel, but similar circuit connections maybe madeserviceable in connection with other mediums having similar .reactions.A pure gas is preferably, however, since it tendsto insure uniformityofthe reactions. I preferato use mercury or mercury vapor in anhenmetically sealed vessel or container. The .container and any solidelectrodes therein, are preferably of such material as not to yieldgases under the conditions of operation. The methods of cleansing andevacuating such devices by washing with mercury vapor and exhausting thesame while subjected to the action of heat and of the electric currentare now well known in the art.

As hereinbefore indicated, the meansfor starting and maintaining current,fiow between the main electrodes of the vapor device may be any ofthose commonly known in the art as suitableor desirable for suchpurpose.

In the accompanying drawings I have shown various forms of vapor devicessupplied with one or moreauxiliary electrodes connected with anindicating instrument in various ways. The variety of-arrangementdisclosed is such as will enable thoseskilled in the art to understandthe nature of'my discovery and to arrange modifications adaptingthe sameto further uses.

In the drawings: Figure 1 shows a simple form of my device in verticalsection and simple circuits therefor in diagram. Fig. 2 is a similarview showing means for rendering the reactions at the main negativeelectrode more stable. Fig. 3 is a similar view of a modificationwherein the positive electrode is arranged close to the negativeelectrode in such manner as to render the reactions at the positiveelectrode more stable. Fig. 4c is a similar view showing the auxiliaryelectrode at the top of the container, and the source of variations asoperatively related to the device by means of a capacity area. Figs. 5,6, 7, and 8 show modified devices With multiple auxiliary electrodes andvarious circuit arrangements in diagram. Figs. 9, 10, 11, and 12 showtwo ring electrodes adjacent the negative electrode. Figs. 13, 14:, 15,and 16 illustrate typical indicating circuit variations, all otherfeatures being identical. Fig. 17 shows further typical indicatingcircuits. Fig. 18 illustrates an indicating circuit connection betweenconcentric auxiliary electrodes. Fig. 19 illustrates an arrangementwherein the indicating circuit contains the primary of a transformer.Fig. 20 shows a vapor device having two positive and two negativeelectrodes, which may be connected up in a multiplicity of wayshereinafter re ferred to. Fig. 21 illustrates a special form of thedevice wherein the positive electrode is adapted to heat a projectionfrom the negative electrode. Fig. 21 is a detail sectional view of amodified arrangement of main electrodes. Fig. 22 illustrates a vapordevice associated with a magnet and arranged'in shunt to the condenserof a close "tuned or resonant circuit inductively associated with aprimary source of variations. Fig. 23 illustrates a special. form ofvapor device having three concentric electrodes of different areas atthe to wf the device and certain connections to befireferred to. Fig. 24illustrates a vapor device having a disk as the positive electrode and aplurality of permanent magnets arranged to modify the internalconditions and reactions.

In various of the figures of the drawings, electrodes of thin materialhaving various outlines, are shown as viewed from a point above theplanes of said electrodes, in order to show the structure more clearly.While any one or more of these electrodesmay be arranged at various,similar or different angles, it is to be understood that theseelectrodes may be and preferably are arranged with their fiat surfaceslying in planes at right angles to the axis of the vapor device. Ineither case, the device is preferably normally operated in a verticalposition, but may be and frequently is operated in a tilted position asdesired, in order to vary internal conditions for particular purposes orconditions.

In the various figures of the drawings, the specific devices embodyingmy invention comprise main positive and negative electrodes, one or moreauxiliary electrodes, and a suitable container. The main electrodes aresupplied with current from a suitable source, preferably a directcurrent source, indicated in the drawings as a storage battery. Thissupply circuit is provided with suitable regulating devices, includingpref-v erably an adjustable ohmic resistance and an inductance which isalso preferably adjustable. The ohmic resistance and the inductance maybe more or less embodied in the same device, but are preferablyseparate. Suitable receiving and indicating circuits are operativelyassociated with the auxiliary electrode.

Like parts have been indicated by like reference characters on thevarious figures wherever this is possible without liability to causeconfusion.

Referring more positive electrode 1 may be of any known or desiredmaterial suitable for the purpose, such as iron, platinum, carbon, orother conducting material. The particular cup shaped electrode shown inthis and other figures, is preferably of the same material, size, andshape as the positive electrode now in general use in the Cooper-Hewittlamps. The negative electrode 2 consists of a body of conducting liquidpreferably of mercury. The auxiliary electrode 3 is preferably a solidconductor of iron, platinum, carbon,

'or other suitable material, though it may consist of a body ofconducting liquid, such as mercury, if desired. The container 4 ispreferably of glass, preferably hermetically able value of impedance,

particularly to Fig. 1", the

sealed and preferablyhaving' a high vacuum when cold. It may be of anysuitable or desired size, and may be conveniently made about 2-1/2 to 3inches in diameter and about 5 or more inches in height. A device ofsuch diameter and 7 inches in height will have a current carryingcapacity through the main electrodes up to 4 or 5 ampere's at pressuresof, say, 7 to 25 volts, and will have ample heat radiating area. Thesource of current supply is shown at 8, an adjustable resistance at 9,and an adjustable inductance at 10. The supply circuit is thus capableof regulation for purposes of controllin the amperage through the lampand for steadgying the same to normally uniform values. The auxiliaryterminal 3 is sensitive to the electrical variations to be detected andthese are operatively applied to the device from any suitable source ofvariation, as, for instance, a receiving wire S of a space telegraph ortelephone system brought in proximity to the device or connecteddirectly to the auxiliary terminal. It will be understood that thevariations to be utilized, may be from other sources and may be ofcomparatively low frequency and greater amperage. Where the variationsto be utilized are feeble or rapid, it is desirable to connect thesupply Wire S to the auxiliary electrode 3 in such manner that thereshall be little capacity or impedance in the sup-11y circuit leading tothe auxiliary electro e. The detecting circuit is preferably arranged'to have a suitthat furnished by a telephone receiver serves well, and atelephone having a resistance of 500 to 2000 ohms is frequently foundsuitable for the purpose of Wireless telegraphy. In case the to. In-Fig. 1 it is shown connected to a capacity area 0, which for spacesignaling purposes need not be very large. A ground connection G issometimes desirable, but not always necessary, and maybe made byconnection from a main electrode, as in Fig. 3, if desired. Where themain direct current supply is from a commercial lighting circuit, suchcircuit may be utilized as a capacity or ground, as in Fig. 23. Thevapor device shown in Fig. 1 is useful for many purposes, but theinternally originated disturbing variations at the electrodes, due tothe passage of the current, are manifest at the auxiliary electrode andtend to obscure its action when minute variations are to be detected.

i Fig. 2 shows a device similar to that in ana-m Fig. 1, but providedwith one of the various possible means for lessenin the internallyoriginated disturbing variations, by rendering the reactions at the mainnegative eleo-' trode more stable. This result is accomplished byarranging a projection 12 extending above the surface of the mercury 2and wetted thereby, after the manner hereinbefore referred to. Aplatinum wire projecting a short distance and having a diameter of .045inch, serves well for this purpose, for currents of from 1-1/4 to 2-1/2amperes 01 even more.

the projection 12 of the negative electrode,

above and preferably parallel with the surface of the mercury 2 andpreferably slightly above said projection. If the ring is used in theform of a fiat disk of iron 1-1/8 inches in external diameter and 1/4inch or less in internal diameter, it will pass 2-1/2 to3 amperes ofcurrent without becoming unduly heated.

' The internal diameter of the ring should not be too great with respectto its distance from the projection 12, for otherwise there may be atendency to unstable reactions giving rise to disturbing fluctuations.Ring electrodes of the above specified sizes, however,

carrying currents as described, are very suitable for the purpose, butthis electrode may be varied in size and shape and may be a disk orother shape. A convenient method of determining or adjusting thedistance of such a positive electrode from the surface of the mercuryconsists in providing the container with a pocket 15 adapted to containan extra supply of mercury 16. In such a device the desired amount ofmercury may be poured oil from the negative electrode into the pocket,or vice versa. In this form of device the starting may be convenientlyeffected by shaking the device so that the mercury of the negativeelectrode momentarily comes in contact with the positive electrode,thereby making and breaking a bridge. With the above describedarrangements, the visible phenomena at the main positive electrode andits resistances are modified and largely suppressed and the attendantdisturbing reactions are made practically unn'oticeable so far asconcerns their effects at the auxiliary electrode and in the indicatorconnected thereto. The device may be operated at a lower potential thanthat of Fig. 1 and it has a much greater current capacity, the latterbeing limited, in practice, mainly by the size and fusibility of thepositive electrode. The heating efiect at the positive electrode is lessas the surface of the positive electrode is increased, and thisarrangement may be used to carry current up to 5 amperes at a voltage of7 to 10 or 12 volts, depending upon the characteristics" of theparticular device. The operation of this form of device, under varyingconditions, seems to vary with the position of the positive electrodewith respect to the negative electrode, particularly for positionsvarying from barely out of contact with the surface of the mercury to,say, 5/8 inch or more from the surface of the mercury.

In Fig. 4 the wireless antenna or other source of variations to bedetected or otherwise utilized, may be connected directly to theauxiliary terminal 13, but is shown as being brought into operativerelation to the vapor device by being connected to a capacity area 0,arranged near the container. This capacity area may be a metal or tinfoil plate a foot or so in diameter and it may be very close to thecontainer or it may be located some inches or even some feet away.

In the arrangement shown in Fig. 3, the auxiliary electrode 13 iscomparatively small in area and is located in the side of the container.For most purposes,'a larger auxiliary electrode 13, located at the topof the container as shown in Fig. 4:, is preferable. This auxiliaryelectrode may be a cup shaped electrode of the same material, size, andshape as the main positive electrode of Fig. 1, which, as I have stated,is like that now in general use in the Cooper-Hewitt lamps.

For some purposes a flat disk such as shown at 13, Fig. 23, ispreferable. The current density in the vapor adjacent such auxil iaryelectrode may be adjusted by changing z the current flow between themain electrodes.

In Figs. 5, 6, 7, and 8, I have shown various forms of containerprovided with main electrodes and with a considerable number ofauxiliary electrodes located in different parts of the container. InFig. 5

the main electrodes are shown at opposite ends of the container, likethose in Fig. 1, but instead of only one auxiliary electrode, there areeight similar electrodes, 3, 3", 3, etc. The figure being a sectionalview shows only three of them in a single plane transversely of thevapor column and near the positive electrode 1, and three more inanother plane parallel with the first, but nearer the negativeelectrode.- In Fig. 6 the arrangement is the same, except that thedevice is provided with a ring electrode 11,

which is utilized as the main positive electrode, after the mannerdescribed in connection with Figs. 3 and 4. 'In this arrangement, theeight auxiliary electrodes are arranged in planes outside of the directpath of current flow between the main electrodes and at differentdistances therefrom. In

this figure the electrode 13 at the top of the container may also beused as an auxillary electrode; In Figs. 7 and 8 the arrangements arerespectively somewhat slmilar to those of Figs. 5 and 6, the principald1ffererence being that in Figs. 7 and 8, the electrodes'in the sameplane are of different sizes. I In Fig. 7 thering electrode 1 1'm a'y beused as an auxiliary electrode and 1n Flg.

8 the cup'shaped electrode 13 at the top of the container maybe used asan auxiliary electrode. In these Figs. 5, 6, 7, and 8, any

one of the electrodes may be used as a single auxiliary-electrode, inconnection with any desired arrangement of indicating'c1r cuit, as, forinstance, after the manner illustrated in Figs. 1 to 4; or saidauxiliary electrodes may be combined in a multiplicity of wayshereinafter more fully set forth. As heretofore explained, there is adesirable current density for the vapor adjacent the auxiliaryelectrode, which is most suitable electrode.

forgiven conditions,"and with devices affording electrcdes'of suchdifferent location and such different areas, a wide range of. selectionis possiblefor each value of cur rent amperage between the mainelectrodes. This range vof selection is vastly increased by the abilityto adjust such ampe'rages to a cup In Figs. 11 and 12 there are two.ring electrodes 31, 32 located one above the'other.

There is also a cup shaped electrode 13 at the top. Either one of thering electrodes or the cup shaped electrode may be used as the mainpositive or as auxiliary electrode or electrodes. When the upper ringelectrode 32, Figs. 11 and 12,.is not used as a main electrode, itappears to serve some useful purpose with. reference to the reactionsoccurring at the main electrodes. One apparent effect is that it tendsto prevent adherent deposits on the Walls of the container, 7

which otherwise frequently occur and which appear to be caused byexfoliations from the. point 12 of the negative electrode.

Figs. 17, 18, 19, and 20 show various forms of vapor device with amultiplicity of solid electrodes. Itwill be understoodthat in all forms,any solid electrode having sufficient area to carry the current, may beused as a main posltlve electrode, and any one or all of theothers usedas auxiliary electrodes.

a liquid nega- 1 For instance, it will be understood withv respect tothe form shown in Fig. 20, that'- either of the lower electrodes 2, 2,may be used as a main negative electrode, either of the solid electrodes1, 1*, or the remainlng liquid electrode being used tive electrode. Insuch case, one or bot of the other two electrodes-a. 0. two solidelectrodes or one solid electrode and one liquid electrode, may be usedas auxiliary as the main osiw electrode'or electrodes in connection withhereinafter indicated.

' I Age will be evident from. the detailed state npent of the nature andobjects of my invention, the vapor device of widely varyingcharaccircuits suitable for utilizingorzindicating these variations arevery numerous. As has been explained in connection with the simplecircuit in Figs. 1 to 4, tions may be connected or brought intooperative relation to the device in such manner that said variationsreach the auxiliary electrode, preferably without being subject to anyconsiderable impedance or reactance. The indicator circuit is theindicating instrument. Such circuit may be connected at the other end toa capacity or a ground, or tothe main negative elecis extraordinarilysensitive in a multiplicity of ways to the elec-j trical variationsteristics of frequency, quantity, etc., and the the source of varia-'any of theindicator circuits hereinbefore or V preferably directlyconnected to the auxiliary electrode and to function, and the best valuethereof should be ascertained by trial when the device is to be used forparticular purposes. In Fig. 13 the indicator B ,may be an elcctromagnetic telephone receiver'having suf icient impedance for the particularpan-pose in view, for instance, 100 to 2000 ohms resistance. Fig. 14illustrates an additional adjustable impedance which may be aninductance coil 29. This is desirable where the indicator itself hassmall impedance, either because of the character of the winding used, orbecause of the nature of the device, as where the indicator is acondenser telephone receiver.. 'It will be understood that suchadjustable impedance may be used in any of the circuits shown herein,but it is usually more desirable that it be in the receiving instrument.In Fig. 15 the electromotive' force the or from theelectrode,

'iliary electrode,'.- and this I used duplicatedwith respect-to an i IQuit glances indicator circuit from the aumliary'terminalito the mainnegativeelee trode iamoraorless counterebalanced, or if ouer balancedzby. the potentiometer 18: shown; The latten'may be adjusted to slightcunt-outflow to'or from-the auxdeviee may be micolmectiom with the otherdevices and circuits shown'herein; In Fig. -16;the arrangement of:circuits is the same, except that-aa-condensers-libis usedasthe snurceofcounter electmmotivefonce in place of the f potentiometen Such,condenser is; a very .practicah. neliabhr and] usefuldevice whereno-normal. current flow inthe' auxiliary terminahis desired Thefunctions of these various devices inpermitting or controllin or.preventing: slight. normal current flow. to heretoforeexplainedz All ofthe connections shown-in Figs. 13,114, 15,,and 16 may be indicator.circonnection-from the auxiliary electrode extending: to the mainpositive electrode, instead. of to the'main' negative electrode. In Fig.17 have shown such connectionv from the auxiliary electrode 13 tothemain positive electrode-ll, acondenser '19 being interposed. betweenthe indicator and the main positive electrode; but it will be understoodthat a potentiometer may be used or a simple impedance may be used, orthe circuit: may bea. simple circuit containing only the indicator.Where a condenser is used after the manner. shown in Fig. l7, it ispreferable that such condenser be between the indicator and the positiveelectrode, rather thanbetween the indicator and the auxiliary Ilheproper valueof the capacity togive the best results for given conditionsis preferably. determined by trial of various v a ues-of capacity, andwhen'the most suitable value has been thus-determined, a nonadjustablecondenser of such capacity may be substituted: The latter isparticularly convenient-and eflicient for wireless indications. Acondenser of 1/4 microfarad may serve well, and one of much lesscapacitymay be used for feeble signals. -.The most desirable capacity for thiscondenser seems to depend upon the length of the wave trains and thespark frequency, but a condenserofsuitable fixed! capacity. will usuallysatisfy practical requirements. V

With this general description ofthe typical circuits-of Figs. 1, 2, 3,4, 13, 14, 15, 16 and 17, it willbe understood that the more complexdevices of Figs. 5,6, '7, 8, 9, 10, 11, 12, 1S and 20 may be connectedup in a multiplicity ofways, all of which are operative and various ofwhich are best suited to particular conditions.

Referring to- Fig. 5, the main circuit is auxiliary.- electrode, hasbeen 7 allelrtoact as-the other terminal of the indicatoroircuit. In:this-arrangement: the two upperau'mharyelectrodes have an arearelated'to the combinedarea of. the electrodes,

astwodstothree, the upper two -electrodes being" located 111- thecontainer fromw-the-lower threeelectrodes.

The circuitshowniin Fig.- dil-lustratesthe act that whene the mainelectrodes are close togethenat the lower end of; the container,anaindimting cimu-it-may be operatively employedqhyconneeting twoelectrodes in a single transverse plane with one electrode differently gof thesam'earea; 1nthe same-plane,-the difference in area between thetwo electrodes and-the one electrode resulting insensitiveness. InFig.7- aismallelectrode in anupper plane of the container is connectedthrough the indicator with-a large electrode inalower plane. In Fig; 8 asmall electrode is connected through the indicator with a largerelectrode in'the same plane. The multiplicity of possible permutationsand combinations of various locations and the values of electromotiveforcefrom one electrode to another andi of the values of mainGllI'IElltlflOW in these devices, is so great as to render specificdetailed demription impractical when the breadth of' utility of thedevice is considered. It is suflicient to say thgiit the widest? rangeof selection: is possi c.

Fig; 9 shows the indicator circuit con nected: between two.- concentricauxiliary ring electrodes 21 22 closely adjacent the main negativeelectrode, the main circuit being-through the cup shaped main positiveelectrode 1' at the top. InFig. l0'the inner ring-electrodeis the mainpositive electrode and: the indicator is connected between the cupshaped upper electrode 13 and the outer ring electrode 22; In- Fig. 11the indicator is connected between the upper cup shaped electrode 13-and the ring electrode32 above the main positive ring electrode-31. InFig.

12 the indicator-connection'is from the upper cup shaped auxiliaryelectrode 13 to the lower ring electrode 31 used as the other auxiliaryelectrode, the upper ring electrode 32 beingused as the main positiveelectrode. A modification of concentric electrodes is shown in- Fig. 18where the upper cup shaped electrode13 is the main positive electrodeand: the indicator: is connected between a small! auxiliary electrode 43and a larger cylindrical electrode 44 concentric therewith, Thecondenser shown at 19 may be used or'not as desired.

In Fig 19 the indicator circuit contains a; primaryP of-a transformer Tand is connected'between the-auxiliary electrode 13 at the upper end ofthe container and the-main .positive electrode 11. The secondary of thetransformer may be connected in circuit T with any desired translatingdevice It. In case a siphon recorder is used mthis secondary clrcuit,the circuit or the recorder may be tuned to the frequency of the1mpulses received therein, wh1ch 1n the case of spark telegraphy, maybe, in some cases a group or spark frequency. In an arrangement such asshown in Fig. 19, the normal current flow through the auxiliaryelectrode was found to be about 1/10 milliamperes when not checked by acondenser, and with a potentiometer 18 interposed and adjusted to givethe proper counter electromotive force, the results, in the case ofwireless telegraph signals, were found to be remarkably good.

Fig. 21 shows a form of device wherein there may be special heatingaction of the positive electrode 11 on the negative electrode when thepositive electrode is so designed with respect to the current flowingtherethrough as to be highly heated. To this end the positive electrodeis made small, so as to become heated by the passage of current from it,and is concentrically arranged around a projection 12 from the negativeelectrode, which it tends to heat, this projection tending to renderstable the negative electrode reactions at its base. Such a positiveelectrode being constructed of platinum wire .057 inch in diameter andwound in a helix, having an inside diameter of 1/4 inch and being of twoturns, will become heated with 1 ampere passing, and will work with 1l/2 amperes, the bottom of the helix being substantially 1/8 inch fromthe level of the mercury.

In Fig. 21 the vapor device is shown with connections to a receivingcircuit which may be useful with other forms of the device.

be a crest of potential at 13.

The receiving conductor S is shown tuned as at 47 to a quarter wavelength and the lateral conductor 45 leading to the electrode 13 of thevapor device is also tuned as at 46 to the same frequency. The groundcon nection G may be adjustable as at 48 and when the latter is used thecircuit Gr, 48, 47, S will be the electrical equivalent of the circuitG, 48, 46, 45, 13, so that there will In Fig. 22 the vapor device isshown as connected through a lateral conductor 54 with a closed tuned orresonant circuit, preferably tuned to-the frequency of the receivedenergy to be detected by means of a suitable adjustable inductance 51and an adjustable condenser 52. The inductance 51 may be a length ofstraight wire, if desired. This closed tuned circuit is associated bymeans of a transformer 53 with a receiving wire S, and the parts may beall designed and operated in accordance with an of the principles wellknown in the art. he lateral conductor is shown adjusted as at 55 to thequarter wave length of the received energy so that there will be aresonant rise of potential at 13". I may, however, use any of thedevices and electric interlinkages now used in the art .of wireless orwire telegraphy or telephony,

and the specific circuits herein shown may. be used in connection withother detectorsl Referring more particularly to the ar rangement of Fig.21, if the auxiliary electrode 13 be a circular plate 1-1/4 inches indiameter and its distance from the mercury negative electrode 2 be fiveinches and the main positive electrode be a ring of iron 1-1/8 inchesoutside diameter having a hole in the center 1/4 to 5/16 inch indiameter and if it be situated 3/8 of an inch from the surface of themercury electrode, the container vessel being substantially from 2-1/2to 3 inches in diameter, and properly exhausted, said vapor device willrespond to extremely faint variations. Its sensitiveness may beincreased byapproaching an ordinary permanent magnet M somewhat in themanner shown in Fig. 22, the distance varying from close proximity tothe device to 18 inches or so from it. A second magnet applied as shownin Fig. 22 may have a beneficial effect in tending to produce aresultant magnetic field wherein the lines of force lying in the pathabove 11 and 12 are at an angle of approximately 45 degrees fromthenormal vertical position of the negative electrode flame.

The various conditions of electrode size and location, main currentflow, etc., may be so adjusted by trial as to cause a whistling sound ora regular note in the telephone when the magnet is at a suitabledistance from the container. By then adjusting one of the variables,preferably the magnet, the device may be put in a critical or unstablecondition, where faint signals may be indicated by perceptible changesin the quality, pitch, or intensity of such sound. In some cases thedevice may be put in a condition where there is little or no perceptiblenote audible and yet the balance is so delicate that the faintestdisturbance, will precipitate the sound of the note, thus giving astrong signal where otherwise the effect might be nearly or quiteinaudible.

The circular auxiliary electrode 13 is shown in Figs. 21 and 23 asflattened and arranged in a transverse plane with the flat surfaceapproximately equidistant from the path'between the main electrodes, sothat almost all of the surface of the electrode exposed to the vaporlies in an approximately equipotential region of suitable currentdensity. This arrangement has certain advantages where it is desired touse a, fine adjustment of counter electromotive force of a potentiometerto secure the most sensitive condition for feeble signals.

One reason for "of such exposed surface may altitude times found to beunsatisfactory for the finest work in connection with the faintestsignals. One probable reason for this is that the condition of mostextreme senstiveness of the auxiliary electrode seems to depend upongetting an extremely fine balance of the counter electromotive force ofthe pot'entiometer against the electrical pressure at the surface of theauxiliary electrode. The latter pressure has for one importantdetermining factor the current density in t e portion of the vapor incontact with the electrode, and it seems to be a fact that if theauxiliary electrode is so formed or arranged that there are materiallydifierent current densities in the vapor adjacent different portions ofits surface, the counter electromotive force of the potentiometer whenset to a proper value for the current density adjacent one portion ofthe exposed surface, will be either too great or too small for otherportions where the adjacent current density is of different value. Onthe other hand, if all portions of the exposed electrode surface areacted upon by vapor of substantially the same current density, thecounter electromotive force may be very accurately adjusted to thatcurrent density, and such adjustment being perfect for one portion ofthe electrode is perfect for any other portion of the electrode. Anotherreason may be that a uniform density of current flow into and out of aconsiderable area of the electrode may be desirable. This result shouldbe accomplished by the above arrangement of the auxiliary electrode,because by it the lengths and resistances of the vapor path fromdifferent portions of the surface of the electrode, will besubstantially equal.

Fig. 23 illustrates an arrangement of three concentric auxiliaryelectrodes 13, 13 and 13 of different areas, preferably in the sameplane, whereby the working surface area of auxiliary electrode may berapidly and conveniently changed where varying indications are to bereceived. In connection with this device is shown a condenser 82interposed in the aerial and having a shunt circuit to ground from thepart of the aerlal above the condenser through a small vapor gap orinductance for tapping off atmospheric charges from the aerial. I haveemployed for this purpose a vacuum tube constructed and arranged verymuch as shown in the drawings. The tube is about 3 inches 'long providedwith disk electrodes 84, 85

and-has a calcium compound therein intended to fluoresce upon passage ofsuitable current between the electrodes, the specific material in thisparticular case being a compound of calcium, probably calcined shells.his device was found to discharge at a pressure as low as 150 volts, andits action appears in no way to interfere with the impulses to bereceived by the receiving apparatus. The current supply between mainelectrodes is indicated as being from a commercial, direct currentgenerator 86, with a shunt storage battery 8 adapted to be chargedthereby.

In Fig. 24 I have shown a modified vapor device of the general type ofconstruction hereinafter described, having an indicating circuit R, 19,between the main positive electrode 11 and the auxiliary electrode 13,and a circuit 8, 9 and 10 acting to supply current through the mainpositive electrode 11 into the main negative electrode 12, 2. Thevariations to be detected or translated are received through the wire64, which may be connected with any desired wire or wireless circuit.The main positive electrode 11 of this vapor device instead of being aring or perforated plate, is a disk or imperforate plate, preferablythin and about 1 to 1-3/16 inches in diameter.- Its size and locationwith respect to the surface of the mercury and projection 12 are muchthe same as in other cases hereinbefore specified. When such disk isused instead of the ring or erforated plate, there are various modications in the phenomena manifested, and the device is particularlysensitive to the influence of a magnetic field. The magnets seem to havethe most marked effect in increasing sensitiveness, when they arearranged close to the container and so related thereto as to cause themagnetic lines from the poles in a plane of the axis of the device. Inthe arrangement shown in 24 the permanent magnets M, M are symmetricallyarranged in the same axial plane of the container with the south poiesof each close to the negative electrode and the north poles close to thewalls of the container about midway thereof and between the mainpositive electrode 11' and the auxiliary electrode 13. Such anarrangement seems to have very marked effect in increasing thesensitiveness of the device and a slight movement of either of the polesof either of the magnets to or from the container or out of diametrica-lsymmetrical relation causes Fig.

far greater changes in the internal efi'ects .Y

manifested in the receiver R, than do corresponding changes in theposition of the magnet M in the case of the perforated plate or ringpositive electrode of Fig. 22.

y experiments show that being equal, the perforated plate or ring otherthings positive electrode of Fig. 22 seems to give smoother efi'ectsmore directly proportional to the received variations, whereas the diskarrangement as shown in Fig. 24 seems to give more distorted ordisproportionally amplified indications. This quality of the disk orimperforate plate seems to render it particularly useful for receivingimpulse signals, Whereas the perforated plate seems to preserve thevalue of the amplified variations more accurately and to be better adapted to translate telephone variations.

In many cases the operation of the device is improved by maintaining aconstant static charge of a desired pressure upon the aerial and uponthe auxiliary electrode. This may be accomplished by using a condenserin the ground connection, Fig. 17, and employing a shunt vacuum devicesuch as shown at 83,

Fig. 23. If then the aerial be charged from the atmosphere or from anysuitable source of potential, the gap at 84, 85 will act as a pressureescape valve to maintain the pressure within desired limits. Thepotential at which this valve will pass current may be modified by anysuitable means as, for instance, by an external source of radioactivity,or ultraviolet or cathode rays.

The device described herein may be designed so as to be used for thepurpose of receiving varying impulses of any frequency or strength andmaking them serviceable on direct current devices. It is also adaptedfor telephonic purposes, particularly for wireless telephony. Foralternating currents the device may be constructed or ar ranged so as tobe asymmetric, and may therefore be connected up either singly or in apair in any of the well known ways, to take advantage of one or bothhalves of the alternating current to produce indications or effects in atelephone or other translating device such as a direct current indicatoror instrument. With certain currents it may be made use of to takeadvantage of certain portions of a wave. The asymmetric resistancecharacteristics of the vapor device when constructed and operated asherein explained, may be made to persist for the highest frequencies aswell as for the lowest voltages, and these characteristics may be reliedupon for the rectification or asymmetric translation of variations of anextremely small fraction of a volt and of the highest frequency, therebyrendering possible the use of a direct cur rent indicating instrument. Ihave found it desirable in order to fully utilize the asymmetricresistance characteristics of the device to so arrange the auxiliaryelectrode that it will act as an approximately no re.-

with respect to oscillations of the strength which it is desired totranslate or detect by such device. When properly designed and arranged,the half waves or impulses coming through such electrode pass off freelyinto the gas or vapor, butthe half waves or impulses tending to run inthe opposite direction are substantially blocked, thus giving therectifying effect necessary for operating the direct current or otherinstrument. This result may be achieved in connection with any of thetypical circuits and devices shown herein. Referring for convenience toFig. 21, the electrode 13 should be located at such distance from themain electrodes 11, 12 that the current flow therefromand the currentdensity of the vapor adjacent thereto is near the point Where normalinternal variations begin to cause disturbing indications in theinstrument R. In a particular case this distance might be somewherebetween 1 and 7 inches or, say, about 5 inches. The distance-should beand in the case mentioned usuallv will be, such that the current densityin the vapor adjacent the auxiliary electrode will not be sufficient toneutralize the opposition or reluctance of such electrode to act as anegative electrode with respect to impulses of the strength which it isdesired to rectify. Under such conditions the flow of current from theauxiliary electrode into the vapor will be measured by a normal voltagedrop at the auxiliary electrode which may be some 1', 2, 3, or morevolts, according to the conditions. The application of electromagnetsafter the manner described in connection with Fig. 22 may serve toreduce this voltage drop to a fraction of a volt, say, for instance, to7/10 volt or less. If now the potentiometer 18 be applied as a source ofcounter electromotive force, this drop may be counterbalanced byadjusting the potentiometer to a pressure of, say, 7/10 volt in theopposite direction. It is a peculiarity of such device, however, that inorder to suppress the effects of internally originatedv disturbances inthe telephone R, the counter electromotive force should be slightlygreater than the original drop, or say somewhere about 75/100 volt,where the drop was found to be 7/10 volt. By still further experimentalrefinement of adjustment of this counter electromotive force, thevoltage drop at the auxiliary electrode may bereduced practically to azero, so that half waves or impulses of the smallest fraction of a volt,say, for instance, 1/10 volt to 1/100 volt, or less, will pass freelyand practically unimpeded into the vapor, whereas the half waves orimpulses tending to run in the opposite direction will be blocked andprevented from passing from the gas into the electrode 13", so that theeffects of the variations are observable in a direct current instrument.The adjustable potentively applying to the tiometer thus arranged,is anaccurate means for attaining at the electrode 13, the conditions whichwill best serve the purpose of detecting alternating currents by adirect current instrument and yet not give rise to undue internallyoriginated disturbances which might tend to mask the effects in theindicator R.

While I have last above described an arrangement or" my device which isparticularly eflicient for rectifying, it will be understood that thedevice is so remarkably sensitive in such a variety of Ways that it willact as a very good detector of feeble varia ons such as arecharacteristic of the receiving wires of ordinary commercial wirelesstelegraph systems, even when the adjustments are such that theasymmetric action is at a minimum.

With reference to magnets, it will be understood that the position andnumber of the magnetic lines and their action with respect to thenegative electrode flame and other phenomena, may be varied byadjustment of any desired number of permanent magnets in a variety ofways. If desired the adjustment of strength of the magnets may beconveniently altered by using electromagnets in place of permanentmagnets. By adjusting either independently or together, the current flowin the solenoids of one or more electromagnets used to produce a singleresultant field, the direction and distribution of the lines of force insaid resultant field may be changed as desired. Permanent magnets orother means for producing a magnetic field may be used to modify currentflow at a positive or atoan auxiliary electrode by being located at suchelectrode or electrodes. A. starting band C of the type well known inthe art may be applied at a main negative electrode, as in Fig. 2, or anauxiliary electrode, and may be used according to the practices wellknown in the art, or may be utilized as a means of operadevice, thevariations to be translated or detected.

lVhile my above described invention contemplates the utilization ofreactions developed by current flow in a circuit which includes a gas orvapor as one of the conducting media, it will be understood that thespecial or auxiliary terminal and the circuit arrangements may beemployed in connec' tion with other conducting media carrying currentsupplied to the medium independently of the auxiliary terminal. Ingeneral the circuits whose reactions are to be utilized, should includedifferently conducting media affording variable electrical reactions ofvarious classes, such as transition resistances, etc. I prefer a trueconductor or conductor of the first class, such as ordinary conductingmetals, and also a conductor of .another class of conductivity at, forinstance, one which is adaptedto pass current after the manner ofelectrolytes or conduct ing fluids such as gases or vapors. A suitablesource of electromotive force should be employed to maintain normalcurrent flow in the circuit of the fluid medium, said current flow beingpreferably of relatively large quantity and low voltage. The indicatorcircuit should be a lateral or branch or parallel circuit including apart only of the fluid medium of said first mentioned circuit.

The source of variations to be translated may be a circuit of eitherforced variations or oscillatory variations and may be an open circuit,connected to ground or a capacity, or not, as desired. A closed circuitof either forced variations or oscillatory variations may be applied toadvantage or any of the arrangements shown in each and all of thefigures of the drawings by connecting the two sides of such closedcircuit in the same way that the aerials S and ground G respectively areconnected, or in any other desired way, all as will be well understoodby those skilled in the art.

In the foregoing description and in the accompanying drawings I havespecifically set forth only a few of the typical and desirable ways ofarranging the aerial, indieating and direct current supply circuits.From these it will be evident to one skilled in the art that my vapordevice is so sensitive that the variations to be detected or translatedcan hardly be applied to the same in such manner as not to produce someeffect on the internal reactions and that those reactions will producemore or less pronounced sensible effects in the indicator whenever thelatter is applied to the vapor device in such manner that impulses,direct currents, or displacement currents may .flow therethrough inresponse to potential variations. The instrument should be designed orlocated' so as not to 'be injured by the amperage of such current flow,and, in general, 1t is preferable to arrange the indicator and variationcircuits in such manner that the variations to be detected may pass tothe vapor device without being impeded or choked out by the indicator.

It will be observed that in the foregoing description of my broadinvention and in the drawings illustrating the same, I have disclosedmany specific devices and 1nventions which while adapted for orancillary to the broad invention claimed herein, are too diverse to beclaimed in detail in a single patent. Hence I have filed threedivislonal or continuing applications Serial Nos. 28,433; 28,434 and28,435, filed May 15th, 1915, wherein I have reserved all divisible orseparately patentable subject matter not specifical'ly claimed herein.

I claim:

1. An apparatus for translating electrical

